Mississippi Cosmetology Board Practice Exam

Hair is primarily composed of a fibrous protein called keratin. This structural protein provides strength, resilience, and protection to the hair. It is arranged in a helical structure that allows it to form strong bonds, contributing to the overall durability of the hair strands.

Unlike enzymatic proteins, which facilitate biochemical reactions, contractile proteins, which are involved in muscle contraction, and globular proteins, which have diverse functions such as transport and catalysis, fibrous proteins are specifically designed for structure and support in cellular and tissue components. The unique properties of fibrous proteins, such as their tensile strength and ability to form tough, protective layers, make them essential for the integrity of hair, skin, and nails. This specialization is why fibrous protein is the correct answer in relation to hair structure.